Oxaliplatin-based therapeutics is a widely used treatment approach for hepatocellular carcinoma (HCC) patients; however, drug resistance poses a significant clinical challenge. Epigenetic modifications have been implicated in the development of drug resistance. In our study, employing siRNA library screening, we identified that silencing the m6A writer METTL3 significantly enhanced the sensitivity to oxaliplatin in both in vivo and in vitro HCC models. Further investigations through combined RNA-seq and non-targeted metabolomics analysis revealed that silencing METTL3 impeded the pentose phosphate pathway (PPP). Mechanistically, METTL3 was found to regulate G6PD, the rate-limiting enzyme of PPP through the ubiquitination-proteasome pathway. To identify the potential E3-liagese of G6PD, we performed co-IP in G6PD-flag exogenous expression Huh7 cells with anti-flag magnetic beads. The enriched protein sample was subjected for MS identification.